Holding system for accessory instruments, especially in minimally invasive surgery

ABSTRACT

A holding and positioning system for locates and moves adjunct surgical accessory instruments relative to a patent&#39;s body during arthroscopic surgery without risking rupture of the patient&#39;s tissue at the instrument access opening in the patient&#39;s body.

TECHNICAL FIELD

[0001] This is a continuation in part of co-pending U.S. Ser. No.09/702,039, filed Oct. 28, 2000.

[0002] The present invention relates to a holding system for surgicalaccessory instruments as they are employed especially in minimallyinvasive surgery, preferably in solo surgery as it is called.

BACKGROUND ART

[0003] For carrying out complex surgical operations in arthroscopy, aplurality of different instruments and optical equipment are required.Such instruments include so-called active instruments, which areactively employed by the operating surgeon for carrying out surgicalmeasures, and passive or accessory instruments which have the functionof enabling the active instruments to be used. Such accessoryinstruments typically include incision flushing devices, opticaldevices, and the like.

[0004] In clinical use the optical equipment and the accessoryinstruments are usually held by an assistant and manipulated upon theoperating surgeon's request. In order to facilitate or replace theassistant's rather static work, holding arms and support devices forholding the primary surgical instruments during the surgical procedureshave been employed in practice and are known from the prior art. Thesurgical instrument holding devices of the prior art are rather complexand are rather difficult to sterilize prior to use. The holding devicesare frequently covered by sterile films during use which furthercomplicates the ability of the surgeon to manipulate them during thesurgery.

[0005] It would be desirable to provide a relatively uncomplicated andeasily sterilized arthroscopic instrument holding device which is sturdyin construction, and can be easily used by the surgeon during thearthroscopy procedure.

DISCLOSURE OF THE INVENTION

[0006] This invention relates to a generic instrument holding systemwhich can be easily sterilized, is easy to position, and can stablysupport and position the surgical trocars in a desired position duringthe arthroscopic surgery. This invention relies on the fact thatinternal body cavity walls, for example, the abdominal wall, has acertain intrinsic elasticity which permits a minimum tension to beimparted to the body cavity wall in the direction of the plane of thebody cavity wall without the risk of rupturing the body cavity wall.This elasticity varies with the age of the subject, but not with thegender of the subject. This allows the stationary pivot point of theinstrument holding devices to be be spaced slightly apart from thepatient's body cavity wall so that the entering point of the body cavitywall through which the surgical instruments are inserted is onlyminimally moved during the surgical procedure due to the instrumentlever arm conditions which are established by the holding device. Thedistance between the stationary pivot point of the instrument and theentry point through the abdominal wall will preferably be between oneand three centimeters, or less. At these distances the extent ofmovement of the tissue at the body cavity entering point does not exceedthe extent of movement that would result in shearing of the body cavitywall, thereby avoiding rupture of the body cavity wall duringmanipulation and positioning of the surgical instruments within the bodycavity. Thus, the spacing between the pivot axis of the holdinginstrument and the subject's body is designed to minimize shearingforces exerted on the subject's abdominal cavity wall, or otheranatomical tissue.

[0007] The positioning of the pivotable swivel part of the holdingdevice away from the body cavity wall enables achievement of aconsiderably simplified design of the instrument holding arm in that theswivel point of the holding arm does not need to be coexistent with theinvariable entry point into the body cavity wall, but the swivel pointinstead can be very close to or located in the area of the holding armwhich engages the surgical instrument during use of the system. Thesystem of this invention enables the use of plural holding andinstrument positioning devices to be used during a surgical arthroscopyprocedure and enables the surgeon better access to the patient than whena surgical assistant is present. The instrument holding system of thisinvention also ensures that the adjunct instruments used in performingthe surgery will be securely held in place relative the incisionsirrespective of the weight of the various adjunct instruments that areneeded during the surgery.

[0008] The invention will be more readily understood from the followingdetailed description of several embodiments thereof when taken inconjunction with the accompanying drawings, in which:

BRIEF DESCRIPTION OF THE DRAWINGS

[0009]FIG. 1 is an end view of one embodiment of an arthroscopyinstrument holding assembly formed in accordance with this invention;

[0010]FIG. 2 is a view similar to FIG. 1 showing the degree of possiblemovement of a trocar which is held in the holding assembly;

[0011]FIG. 2a is a perspective view of another embodiment of anarthroscopy instrument-holding device formed in accordance with thisinvention;

[0012]FIG. 2b is a perspective view of yet another embodiment of aholding device formed in accordance with this invention;

[0013]FIG. 3 is a fragmented perspective view of a cluster of theinstrument-holding devices formed in accordance with this invention;

[0014]FIG. 4 is a diagram showing the relationship between tensile loadand stretching of individual parts of a human body; and

[0015]FIG. 5 is a diagram which shows the relative tensile strength andtissue stretching of human beings in various age groups.

DETAILED DESCRIPTION OF THE INVENTION

[0016] Referring now to FIGS. 1 and 2, the holding and positioningdevice for surgical accessory instruments formed in accordance with thisinvention comprises an arm 1 which may be sufficiently elastic toprevent tearing of tissue which forms an incision through which thesurgical instruments are inserted into a patient's body. The arm 1 canbe made from a coil spring A which has the necessary inherentelasticity, or the arm 1 can include joints B that are imparted with thedesired elasticity by means of torsion springs C or elastomeric gasketsD. The support frame 2 is a U-shaped yoke having mounting bases 2 a atopposite ends thereof. The mounting bases 2 a form parallel planarsurfaces 2 b which are spaced a predetermined distance apart from eachother. The mounting bases 2 a are penetrated by bores or through holes 2c which are located substantially in the center of the respectivemounting bases 2 a and are aligned coaxially with each other. In theleft-hand bore there is located a support and actuating journal 6 of afirst retaining/fixing die 4. The actuating and support journal 6projects from the outer surface of the support frame 2 and forms a linkwith one end of an actuating lever 5. The first retaining/fixing die 4has the form of a cylindrical piston and includes a concave engagingsurface 4 b in its face that is remote from the support journal 6.

[0017] At the opposite mounting base 2 a on the right hand side of theyoke 2, there is a second retaining/fixing die 4 a which includes acylindrical piston portion having an inner concave engaging surface 4 band an outer support journal 7 which is positioned in the bore 2 c ofthe die 4 a. The journal 7 includes a outer groove in which a retainersnap ring 8 is mounted. Alternatively, the journal 7 could be glued,pressed or otherwise secured in the bore 2 c. A receiving ball 3 forms aseat for the surgical instruments and defines the pivot point or axis ofthe holding and positioning device of this invention. The ball 3 has acentral through bore 3 a which is located between the two dies 4 and 4a. The ball 3 has a radius which is smaller than the inner radius of theU-shaped support frame 2 so that it is held in position by the twoopposed retaining dies 4, 4 a. It will be noted from FIG. 1 that theretaining/fixing die 4 can be axially displaced along the journal 6 bythe actuating lever 5 so as to thereby vary the fixing force applied tothe ball 3 to increase the ball-clamping force so that the frictionalforce between the ball surface and the concave faces of the dies 4, 4 aso that the ball 3 will be prevented from rotating in the die socket. Itshould be noted in this context that the one support journal 6 which iscoupled with the actuating lever 5 could be a screw which could betightened and loosened by means of the actuating lever 5. Alternatively,this support journal 6 could be a bolt having a spring surrounding thesame which biases the support journal 6 and the integrally formedretaining/fixing die 4 in the direction of the ball 3 with the actuatinglever 5 acting, for instance, upon the spring for adjusting the biasingforce. In FIG. 2, the arm 1 is shown in a partially broken view seenobliquely from the front.

[0018] The ball 3 can be rotated and swiveled within a swivel rangebetween the two dies 4 and 4 a, wherein an instrument (not shown) whichis inserted through the central ball bore 3 a can be moved to variouspositions which are described by a cone C which is schematicallyrepresented in FIG. 2. In order to protect against body cavity walltearing while providing a useful degree of instrument movement, the coneangle A may be restricted to an angle which is no greater than about35°. The swivel point of the ball 3 is located on the center linedefined by the two dies 4 and 4 a, and is disposed between the two dies4 and 4 a. The ball bore 3 a is preferably provided with two axiallyspaced radial grooves 3 b in which elastomeric retaining or packingrings 3 c are inserted. These packing rings 3 c, by reason of theirelasticity, exert a clamping force on an instrument, such as a trocar orthe like, which is inserted into the central through bore 3 a in theball 3. In addition, there may be provided a fixing element such as aclamping screw, or the like, which is screwed into the ball and bearsagainst the instrument.

[0019] The assembly operates as follows. First, an accessory instrument,for example a trocar, to be employed in the surgery is inserted into thethrough bore 3 a. The instrument is then introduced into the body of apatient to be treated through a body cavity wall of the patient bypositioning the ball 3 above the instrument body cavity wall enteringpoint, and then axially moving the instrument through the bore 3 a aninto the body cavity to an appropriate location, i.e., a properdistance, as noted above, away from the body cavity wall entering point,and then swiveling the instrument into a position within the body cavitydesired by the surgeon. The instrument can be manually slid and rotatedinside the through bore 3 a overcoming the clamping force exerted on theinstrument by the packing rings 3 c, while the ball 3 can be rotated andswiveled between the two dies 4, 4 a. When the accessory instrument isproperly positioned, it will be held in place by the packing rings 3 c,and also by some additional clamping device such as a clamping screw.For finally fixing the accessory instrument in the desired position, theoperating surgeon will manipulate the locking lever 5 so as to increasethe force applied to the ball 3 by the clamping dies 4 and 4 a and, inso doing, to clamp the ball 3 against further movement. Clamping of theball 3 ensures that the established cone angle A will not accidentallyexceed it's maximum of about 350. In order to reorient the ball 3 andthe instrument connected thereto during the surgical procedure, thesurgeon need merely manipulate the lever 5 so as to loosen the clampingforce on the ball 3 and then swivel the ball 3 in an appropriate manner.Once the ball 3 is properly repositioned, the lever 5 is manipulated tore-clamp the ball 3 in its new position. In use during a surgicalprocedure, the ball 3 will be positioned very close to, or even incontact with the patient's skin, adjacent to the surgical incision intothe body cavity in question. As noted above, the arm 1 preferably canpossess a certain intrinsic elasticity so that swiveling movement of theball 3, and thus the instrument, which is caused by manipulating the arm1 to swivel the ball 3 will not result in rupturing of the body cavitywall by the instrument due to the elasticity of the arm 1. The degree ofelasticity of the arm 1 can be related to the shear strength of the bodycavity wall in question. In its simplest form, the arm 1 could be formedfrom a coil spring having a known elasticity which is determined by theknown tensile strength of the body part, and patient age, being dealtwith in the surgical procedure in question. Referring now to FIGS. 2aand 2 b, there are shown alternative embodiments of mechanisms forholding an auxiliary arthroscopy instrument in place in a body cavityduring arthroscopic surgery. Each of the embodiments shown in FIGS. 2aand 2 b includes a U-shaped yoke 2 which is rotatable about an arm 1that is operably connected to the yoke 2. Each of the embodiments shownin FIGS. 2a and 2 b further includes an instrument support member 3which is pivotable about a support rod 6, and which includes a throughpassage 3 a into which the auxiliary surgical instrument (not shown) isinserted. In the embodiment shown in FIG. 2b, the yoke 2 is furtherpivotable about a support rod 6 a which is mounted in a secondary yoke21, and is perpendicular to the support rod 6. In each of theembodiments shown in FIGS. 2a and 2 b, the instrument support member 3is selectively movable to an operating position so that the instrumentcan be properly positioned in the patient's body cavity during thesurgery.

[0020] Referring now to FIG. 3, there is shown an assembly of theabove-described design which includes the system of FIGS. 1 and 2, forfixing an accessory surgical instrument in a trocar 10 that receives theadjunct surgical instrument which can be an optical, or other adjunctsurgical instrument 11. The trocar 10 comprises an elongated cylindricalreceiving tube into which an adjunct surgical instrument 11 can beinserted. The adjunct surgical instruments 11 to be used are introducedby means of such trocars 10 into the body cavity of a patient beingtreated. The trocar 10 further has the function of keeping open anaccess to the body cavity during a change of adjunct instruments 11. Thetrocars 10 are held in fixed positions relative to the surgicalincisions by the holding and positioning devices described above. Oncethe instrument 11 is properly positioned in the trocar 10 and the bodycavity, the instrument 11 will be clamped in place as describedhereinafter.

[0021] As noted in FIG. 3, an instrument-holding assembly 22 includes abridge 13 having collars 14 and 15 secured to opposite ends thereof. Thecollar 15 has a through bore whose diameter substantially corresponds tothe outer diameter of the trocar 10 or is slightly larger. The collar 14is provided with a through bore whose diameter is equal to or slightlylarger than the outer diameter of the instrument 11. Preferably thecollar 15 is formed with a pair of pivoting opposed jaws 15 a and 15 bwhereby the trocar 10 can be laterally inserted into the through collarbore and the jaws 15 a and 15 b can be moved toward each other as shownin FIG. 3 to clamp the trocar 10 in place. The two jaws 15 a and 15 bcould also be connected to each other by screws (not shown). The othercollar 14 having the through bore which is sized for receiving andguiding the instrument 11 is provided with a clamping screw 16 includingan actuating lever 17, which screw 16 is laterally threaded into thecollar 14 or above the collar 14 into the bridge 13 and laterallyextends into the through bore in the collar 14.

[0022] The assembly shown in FIG. 3 operates as follows. First, thecollar 15 is clamped onto the trocar 10 prior to introducing the trocar10 into the body cavity of the patient. It will be understood that thepatient is positioned to the right hand side of the assembly as shown inFIG. 3. The trocar 10 is then inserted into the body cavity of thepatient. The instrument 11 is then inserted into the trocar 10 and isslid through the trocar 10 and into the patent's body cavity until itreaches the degree of insertion desired by the surgeon. Then theclamping screw 16 is tightened down on the instrument 11 so that thelatter is held in place in the trocar 10 in a manner which does notdamage the instrument 11. During the insertion operation, thepositioning ball 3 will be held in place above the body cavity incisionin a manner which has been described above.

[0023] Referring now to FIGS. 4 and 5 there are shown diagrams or tableswhich show the relationship between tensile load and stretching ofindividual parts of the human body, and also indicate that the tensilestrength of various parts of the human body are age-dependent, and notgender-dependent.

[0024] The flexibility of the swivel arm 1 can be controlled in severaldifferent ways. One, as noted above, is to make the swivel arm from amaterial A which has a known flexibility which is less than the tensilestrength of the body tissue involved. Thus, the swivel arm will bendbefore the tensile strength of the body tissue is exceeded, thuspreventing tearing of the body tissue. Another way to control theflexibility of the swivel arm 1 is to form the swivel arm 1 with jointsB that can be selectively tightened or provided with torsion springs C,or with elastomeric O-rings D that will provide a predeterminedflexibility or elasticity to the swivel arm 1. This elasticity orflexibility can thus thus be pre-adjusted so that the maximum stretchingthreshold of the tissue in question will never be reached, even forsubjects that are in the seventy year plus age range. Thus, the devicewill never tear body tissue which it encounters, no matter what the ageof the subject is.

[0025] It will be readily appreciated that the system of this inventionallows a surgeon to perform arthroscopic surgery on a patient withoutthe need for attendants who maneuver the adjunct instruments used in thesurgery. It also ensures that manipulation of the surgical instrumentswill not result in rupture of body tissue which the instrumentsencounter during the surgical procedure. There are several ways toprevent tissue rupture during use of the system of this invention. Oneway is to place the swivel point of the holding device very close to thepatient upon whom the surgery is being performed; another is to limitthe pivoting cone angle of the holding device; and yet another is toimpart a predetermined elasticity to a part of the holding device thatis used to alter the angular position of the surgical instruments.Obviously, one or more of the these approaches can be used at the sametime.

[0026] Since many changes and variations of the disclosed embodiments ofthe invention may be made without departing from the inventive concept,it is not intended to limit the invention otherwise than as required bythe appended claims.

What is claimed is:
 1. A holding and positioning assembly for securingsurgical accessory instruments in place during surgery, said assemblycomprising a swiveling and rotatable seat for the accessory instruments,said seat including means for gripping the instruments and said seatbeing linked to a mechanical arm via a multi-directonally movable jointmechanism, said mechanical arm being operative to prevent body cavitywall rupture during orientation of the instrument in the body cavity,and said mechanical arm being manually maneuverable to alter theposition of said seat in said assembly.
 2. The assembly of claim 1wherein said mechanical arm is sufficiently elastic so as to bend beforethe tensile strength of the tissue of a surgical patient is reachedduring maneuvering of the assembly during surgery.
 3. The assembly ofclaim 2 wherein the elasticity of said mechanical arm is controlled bythe material that said mechanical arm is formed from.
 4. The assembly ofclaim 2 wherein the elasticity of said mechanical arm is the result ofswiveling joints formed in said mechanical arm.
 5. The assembly of claim4 wherein said swiveling joints are biased by torsion springs.
 6. Theassembly of claim 4 wherein said swiveling joints include elastomericcomponents.
 7. The assembly of claim 1 wherein rupture of the bodycavity wall is prevented by restricting the degree of operative motionof said mechanical arm.
 8. The assembly of claim 8 wherein the degree ofoperative motion of said mechanical arm is restricted to a cone havingan included angle of no more than about
 350. 9. A method of using aholding and positioning assembly for securing surgical accessoryinstruments in place during surgery, said assembly comprising aswiveling and rotatable seat for the accessory instruments, said seatincluding means for gripping the instruments and said seat being linkedto a mechanical arm via a mult-directionally movable joint mechanismwhich mechanical arm being manually maneuverable to alter the positionof said seat in said assembly, said method including the step ofpositioning said swiveling and rotatable seat a distance from anincision in a patient during surgery, which distance is about 3 cm orless so as to prevent rupture of a patient's tissue during movement ofsaid mechanical arm during surgery.
 10. The method of claim 9 comprisingthe further step of limiting the range of possible motion of saidmechanical arm to a cone having an included angle of about 35° or less.